my second was more painful... most my injects go to my thighs too. the third time i started to feel less pain... a couple times after that it only hurt when i hit some nerve endings but they die off... now i feel no pain... prop doesnt hurt anymore, just leaves me a numb knot for a couple days.

I haven't found any real pattern for this. It all depends on how the injection goes in, what you are injecting, if you hit a nerve, or run through a vein. Sometimes you will twich, sometimes you won't. Sometimes blood will shoot out when you are done, sometimes it won't. Sometimes the ones that hurt going in, don't hurt the next day. Soemtimes the ones that you can't even tell you injected leave you sore for a week. Keep it sterile, put the pin in straight, and do the best job that you can and hope for the best.